One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(9,10)(11,21)(12,25)(13,30)(14,32)(15,20)(16,24)(17,28)(18,31)(19,22)(23,38)(26,37)(27,35)(29,36)(33,39)(34,40) involution — undirected(9,11,22,31,15,13,14,24)(10,16,32,30,20,18,19,21)(12,23,29,40,28,26,27,39)(17,34,36,38,25,33,35,37)(2,5)(6,8)(9,12)(10,17)(11,23)(13,26)(14,29)(15,28)(16,33)(18,34)(19,36)(20,25)(21,37)(22,27)(24,40)(30,38)(31,39)(32,35) involution — undirected(1,3,4,7)(2,6,5,8)(9,13,15,11)(10,18,20,16)(12,26,28,23)(14,24,22,31)(17,34,25,33)(19,21,32,30)(27,39,29,40)(35,38,36,37)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.